Terminal block mounting means for plug-in type photoelectric cell



' Aug. 13, 1968 H EGE 3,397,320

TERMINAL BLOCK MOUbiTING MEANS FOR PLUG-IN TYPE PHOTOELECTRIC CELL FiledOct. 21, 1965 I I i /2 592 3 9 5 /6 45 373 f J4 40 4 1 5 CT I l7 1 4/ AD6 m1 4/ A5 4E [rave/i37 United States Patent Wee 3,397,320 TERMINALBLOCK MOUNTING MEANS FOR PLUG-IN TYPE PHOTOELECTRIC CELL Hans Ege,Chicago, 111., assignor to Underwriters Safety Device (30., Chicago,111., a corporation of Illinois Filed Oct. 21, 1965, Ser. No. 499,618 4Claims. (Cl. 250-239) This invention relates to electrical socketmountings and more specifically is directed to a novel means for blindmounting of a terminal block in a manner to permit easy orientation forlater positioning of a plug-in type photoelectric control unit.

Modern control for lighting arrangements, and especially street lightingsystem, include a photoelectric control unit which is sensitive tonatural light conditions prevailing externally of the street lightcontrolled by the unit. Such photocell units are of known type and havebeen used to a wide degree to automatically regulate the operation of aspecific lighting system. When the intensity of natural light diminishesto a predetermined point, the photoelectric cell is operative to turn onor turn off the street light or a series of such lights.

In order for such photocell unit to work in a predetermined manner, itis necessary to orient it with respect to the direction in which the sunrises and sets. Inasmuch as the photoelectric cell unit itself issubject to failure and must be replaced from time to time, the terminalblock or socket mounting of the photoelectric cell should also beappropriately designed and oriented so that photocell may be merelyplugged into the terminal block and locked into position by known typesof co-operating male and female connector blades. It is also desirableto protect the connector blades from the weather as such exposure has atendency to corrode them, causing poor conductance. It is also desirableto have a mounting means for such terminal block which permits expedientinstallation into a socket receiving member, and subsequent orientationof the terminal block immediately prior to final tightening of thefasteners mounting the same.

Briefly stated, the present invention includes a terminal block having abody portion with a radially extending flange at one end. Suitable camsurfaces are formed on the opposite end of the terminal block andco-operate with axially movable cam follower members to cause aspreading of the cam follower members in response to tightening offasteners which extend through the radially extending flange. As thefasteners are rotated, the cam followers engage the co-operating carnsurfaces to extend a socket engaging portion on the cam followers andgrip a shoulder in a socket mounting bore. Suflicient axial travel onthe fastener is available so that the cam followers may be collapsedradially inwardly over the end of the terminal block for blind insertioninto a stepped bore formed in the socket member. The fasteners are thentightened, drawing the cam followers to the cam surfaces and causing aspreading action of the cam followers whereby they will engage ashoulder formed in the bore. The terminal block may be oriented toposition a mark embossed on the flange to the indicated direction priorto drawing the fasteners up tight. After orienting the terminal block,the fasteners are tightened to rigidly and securely mount the terminalblock in the mounting socket. The photoelectric cell unit may then beplugged in and locked into place with a slight twist, squeezing anannular gasket mounted in the photoelectric cell unit against the flangeon the terminal block to seal the parts against the elements.

Details of the present invention will be best understood uponconsideration of the objects achieved and a detailed description of apreferred form.

3,397,320 Patented Aug. 13, 1968 It is an object of this invention toprovide a new and improved terminal block mounting for quick and easypositioning in a stepped bore in a socket member.

It is a further object of this invention to provide a new and improvedterminal block having a novel fastening means which permits blindinsertion and subsequent orientation of the terminal block in a sockethaving a stepped bore thereby to properly orient a photoelectric cellunit which is plugged into the terminal block.

Additional objects and advantages will become apparent when reference ismade to the accompanying drawings in which:

FIG. 1 is a perspective view of the terminal block and photocell controlunit with the two in assembled relation;

FIG. 2 is a cross sectional view of the terminal block of FIG. 1 withthe photoelectric cell control unit partially in section and themounting fasteners in a loose condition;

FIG. 3 is a plan view taken along the lines 3-3 of FIG. 2;

FIG. 4 is an elevational view partly in section of the terminal blockbeing installed in a stepped bore in a socket; and

FIG. 5 is a partially sectioned view of the terminal block assembledinto the socket portions with the photoelectric cell unit in the processof being inserted into the mounted terminal block.

Referring now to FIG. 1, reference character 10 indicates aphotoelectric control unit of the type described briefly above includinga terminal block 11 and photocell unit 12. As seen in FIGS. 1 and 2, theterminal block 11 includes a body portion 13 having a transverse endsurface 14 at one end and a laterally projecting flange 15 at theopposite end defining a lower end surface 16 formed with slot-likeopenings 17-19 to receive male conductors of known form mounted on thephotosensitive control unit 12.

As best seen in FIGS. 1 and 2, the body portion 13 of the terminal block11 may be formed from two parts 20 and 21 joined together by an eyeletor rivet 22 extending through co-operating bores 23 and 24 in each ofthe parts. The slot-like opening .19 merges with an enlarged bore 25having a combination blade and lead female connector 26 positionedtherein. This construction is of known form and may be of the typedescribed in my corresponding application, Ser. No. 205,455, filed June26, 1962, which is now US. Patent No. 3,237,148, issued Feb. 22, 1966,the disclosure of which is incorporated by reference. The lead portionof the female connector 26 is mounted in a bore 27 formed in the upperbody portion 20 of the terminal block 11 and an electrical wire 28 isconductingly attached while the free end (not shown) is adapted toreceive a quick-type connector for operative installation in the socketunit of known form.

The photocell unit 12 illustrated has three male connector blades whichare received in the slot-like openings 1719 with the larger blade 30shown in the cross sectional view of FIG. 2. The male connector bladesare of conventional design being generally flagor inverted L-shaped forinsertion and rotational locking with the female connector 26-. Inasmuchas the male connector blade 30 is of larger angular dimension than theother connectors, the photoelectric cell 12 can only be installed in oneposition. An angular flange 31 on the cell 12 embraces the outer marginof the radial flange 15 and serves to position a gasket member 32 foroperative engagement with the end surface 16 to seal against theweather. The upper end of the flange 31 is adapted for close positioningrelative to the socket member when the terminal block is installed.

Two radially directed groove portions 33 and 34 are formed in the upperend 14 and the bottom wall surfaces 35 and 36 disposed angularlyrelative to the central axis of the terminal block to form cam surfacesextending from the transverse end surface 14 outwardly to thecircumferential surface of the body portion 20. A pair of cam followermembers 37 and 38 have angularly disposed cam follower portions 39 and40 engageable with the cam surfaces 35 and 36. Each cam follower member37 and 38 is apertured and internally threaded to receive threadedfasteners 41 and 42. The outer margin of the cam follower members 37 and38 are adapted to engage a radially directed shoulder 46 formed in thebore of a socket 43 shown at cross section in FIG. 5. Socket 43 isprovided with a first bore 44 coaxially arranged with a second bore 45of increased diameter with the bores joined by the radially directedshoulder 46. Each of the fasteners 41 and 42 extends through the flange15 in longitudinal alignment with the camming surfaces 35 and 36 formedin the body 13 of the terminal block 11.

The terminal block 11 is prepared for installation by loosening thefasteners 41 and 42 and cam followers 37 and 38 to the condition shownin FIG. 2. The terminal block 11 may then be inserted into the firstbore 44 to project partially into the second bore 45 as shown in FIG. 4,where the cam follower members 37 and 38 are positioned well above theradial shoulder 46 joining the two bores. Fasteners 41 and 42 are thenrotated by means of a tool such as a standard screwdriver, drawing thecam follower members 37 and 38 against cam surfaces 35 and 36 formed inthe terminal block. After the cam followers 37 and 38 engage the camsurfaces 35 and 36 and tightening of the fasteners 41 and 42 iscontinued, the cam followers move radially outward to the position shownin FIG. 5 with the outer edges of the followers 37 and 38 overlying theradial shoulder 46 to securely mount the terminal block 11. The axialdimension between the cam surfaces 35 and 36 and the radial flange 15 issuch that the flange 15 and cam follower members 37 and 38 firmly gripthe socket 43 to tightly mount the terminal block 11. Prior to finaltightening, the terminal block may be rotated to orient the arrow shownon the end surface 16 in FIG. 3 to the proper position, which as shownis to be pointed north.

The photoelectric unit 12 may then be installed by positioning the blademembers in the slot-like openings 17-19 and rotating it angularly tolock it in place, causing the gasket 32 to be compressed. Since theterminal block 11 has been properly oriented, the photocell will also beproperly oriented since it may be installed in only one position. Theupper end of the flange 31 is disposed closely adjacent the underside ofthe socket to form a barrier which assists the gasket 32 in excludingthe weather, which could cause corrosion and failure of the electricalconnections.

The novel manner of mounting the terminal block of the present inventionpermits it to be blindly installed and precisely oriented to the properlocation for ultimate positioning of a plug-in type photocell unit withunequaled case. While two cam surfaces have been illustrated, it isobvious that a greater or lesser number may be provided, depending uponthe particular size of the terminal block and corresponding socketmember. The present design provides an easy method of blind installationfor electrical receptacles and especially those designs which must beoriented relative to compass directions.

Upon a consideration of the foregoing, it will become obvious to thoseskilled in the art that various modifications may be made withoutdeparting from the invention embodied herein. Therefore, only suchlimitations should be imposed as are indicated by the spirit and scopeof the appended claims.

I claim:

1. A terminal block particularly adapted for blind insertion into amounting socket, said terminal block comprising a body portion having atransverse surface at one end and a laterally projecting flange at anopposite end, a plurality of terminal openings at said opposite endadapted to receive connectors projecting from a photoelectric cell unit,a pair of cam surfaces formed on opposite sides of said body, a pair ofelongated fasteners extending through said laterally projecting flangein substantial longitudinal alignment with each of said cam surfaces, acam follower member disposed over each of said cam surfaces, threadmeans formed in each of said cam follower members, each of said threadmeans co operating with thread means formed on each of said elongatedfasteners whereby rotation of said fasteners will cause said camfollower members to be drawn into engagement with said cam surfaces, andmeans on said cam follower adapted to engage a portion of said mountingsocket for rigidly mounting said terminal block therein.

2. The terminal block of claim 1 wherein said cam surfaces extend fromsaid transverse upper end surface to a circumferential portion of saidbody portion.

3. A blind mounting arrangement for a terminal block comprising a socketmember having a first bore communicating with a second bore of increaseddiameter relative to said first bore, shoulder means joining said bores,a terminal block received in said socket member and having a portionthereof projecting into said second bore, flange means formed on one endof said terminal block, said flange means being of greater diameter thansaid first bore to cover the same when said terminal block is fullyinserted in said socket, means to mount said terminal block in saidsocket, said mounting means including at least one cam surface formed inthe body of said terminal block, cam follower means engageable with saidsurface and having a portion thereof engageable with said shoulderjoining said first and second bores, and fastener means extendingthrough said flange into threaded engagement with said cam followermeans and operatively urging said cam follower means into engagementwith said cam surface in said body of said terminal block thereby tocause said portion to project laterally from said body and engage theshoulder joining said first and second bores and draw said flange intotight engagement with said socket.

4. The blind mounting arrangement of claim 3 wherein a photoelectriccontrol unit is plugged into said terminal block, said control unithaving a circumferential axially projecting flange disposed closelyadjacent said socket externally of said terminal block flange, andgasket means interposed between said terminal block flange and saidphotoelectric control unit.

References Cited UNITED STATES PATENTS 1,117,084 11/1914 Phelps 3391263,187,294- 6/1965 Murray et al 250-239 X JAMES W. LAWRENCE, PrimaryExaminer. V. LAFRANCHI, Assistant Examiner.

1. A TERMINAL BLOCK PARTICULARLY ADAPTED FOR BLIND INSERTION INTO AMOUNTING SOCKET, SAID TERMINAL BLOCK COMPRISING A BODY PORTION HAVING ATRANSVERSE SURFACE AT ONE END AND A LATERALLY PROJECTING FLANGE AT ANOPPOSITE END, A PLURALITY OF TERMINAL OPENINGS AT SAID OPPOSITE ENDADAPTED TO RECEIVE CONNECTORS PROJECTING FROM A PHOTOELELCTRIC CELLUNIT, A PAIR OF CAM SURFACES FORMED ON OPPOSITE SIDES OF SAID BODY, APAIR OF ELEONGATED FASTENERS EXTENDING THROUGH SAID LATERALLY PROJECTINGFLANGE IN SUBSTANTIAL LONGITUDINAL ALIGNMEMT WITH EACH OF SAID CAMSURFACES, A CAM FOLLOWER MEMBER DISPOSED OVER EACH OF